DIGI TA L C O M PU T E R V Vol 13 No 4 and Vol 14 Nos I 2 •_ D D Gordon D Goldstein Edit S CONTENTS EIOILNOTICES 1 Editorial Policy a O January 1962 il ' OCT 16 1969 CONENT 2 Policy for Contributions 3 Circulation Policy i4 - Ige ULL o 1 1 COMPUTERS AND DATA PROCESSORS NORTH AMERICA 1 Lincoln Laboratory Massachusetts Institute of Technology FX-l Lexington 73 Massachusetts 2 Lincoln Laboratory Massachusetts Institute of Technology Computer Development Lexington 73 Massachusetts 3 Thompson laemo Wooldridge AN UYK- 1 A New Standard Navy Computer Canoga Park California 4 U S Naval Training Device Center UDOFTT Modifications Port Washington New York 5 Univac Division Sperry Rand Corporation Naval Tactical Data 1 3 5 6 System St Paul Minnesota 6 7 Western Reserve University GE ZZ5 and Information Retrieval Cleveland 6 Ohio 8 COMPUTILG CENTERS 1 Daystrom Inc NORC Memory Performance Archbald Pennsylvania 2 National Bureau of Standards Computer Simulation of City Traffic Washington 25 D C 3 New York University AEC Computing and Applied Mathematics Center New York New York 4 TRW Computers Company Computer Traffic Control Canoga Park California 5 United States Army Chemical Corps Biological Laboratories Does All Interpretative Routine Fort Detrick Maryland 6 U S Department of Health Education and Welfare MEDLARS Information Storage and Retrieval System Washington 25 D C 7 U S Naval Ordnance Laboratory Digital Computer Division 8 9 8 9 11 11 13 14 Corona California 14 U S Naval Weapons Laboratory Computation Center Dahigren Virginia U S Navy David Taylor Model Basin Aerodynamics Laboratory Washington 7 D C 15 15 COMPUTERS AND CENTERS OVERSEAS 1 Facit Electronics AB Algol 60 Compiler Soina 1 Sweden 2 Ferranti Ltd Atlas Manchester k London England 3 Institut Ftir Angewandte Mathernatik Johannes Gutenberg-Universitat 4 16 16 Mainz Algol Mainz Germany 17 Norwegian Defence Research Establishment New Computer Lillestr6m Norway is MISCELLANEOUS 1 Bureau of the Census Floating Punch Keypunch Washington 25 D C 2 University of Illinois Plato 11 Urbana Illinois The issuance of this publication Approved by the Secretary of the Navy 25 September 1961 Reproduced by the CLEARINGHOUSE for Federal Scientific Technical Information Springfield Va 22151 L 18 NAVEXOS P1645 - I 18 11UH cad sale ANl ' I lik I EDITORIAL NOTICES EDITORIAL POLICY suggestions to the editor for future issues Matorial for specific issues must be received by the editor at least one month in advance It is often impossible for the editor because of limited time and personnel to acknowledge individually all material received The Digital Computer Newsletter although a Department of the Navy publication is not restricted to the publication of Navy-originated material The Office of Naval Research wel comes contributions to the Newsletter from any source The Newsletter is subjected to certain limitations in size which prevent pub lishingall the material received However items which are not printed are kept on file and are made available to interested personnel within the Government CIRCULATION POLICY The Newsletter is distributed without charge to interested military and government agencies to contractors for the Federal Government and to contributors of material for publication DCN is published quarterly January April July and October Material for specific issues must be received by the editor at least one month in advance For many years in addition to the ONR initial distribution the Newsletter was reprinted by the Association for Computing Machinery as a supplement to their Journal and more recently as a supplement to their Communications The Association decided that their Communications could better serve its mer ers by concentrating on ACM editorial material Accordingly effective with the combined January-April 1961 issue the Newsletter became available only by direct distribution from the Office of Naval Research lt is to be noted that the publication of information pertaining to commercial products does not in any way imply Navy approval of those products nor does it mean that Navy vouches for the accuracy of the statements made by the various contributors The information contained herein is to be considered only as being representative of the state-ofthe-art and not as the sole product or technique available Requests to receive the Newsletter regularly should be submitted to the editor Contractors of the Federal Government should reference applicable contracts in their requests POLICY FOR CONTRIBUTIONS The Office of Naval Research welcomes contributions to the Newsletter from any source Your contributions will provide assistance in improving the contents of the publication thereby making it an even better medium for the exchange of information between government laboratories academic institutions and industry It is hoped that the readers will participate to an even greater extent than in the past in transmitting technical material and All communications pertaining to the Newsletter should be addressed to GORDON D GOLDSTEIN Editor Digital Computer Newsletter Informations Systems Branch Office of Naval Research Washington 25 D C COMPUTERS AND DATA PROCESSORS NORTH AMERICA FX-l-LINCOLN LABORATORY MASSACHUSETTS INSTITUTE OF TECHNOLOGY LEXINGTON 73 MASS important respect a working model for a new generation of machines ten times faster than any computers in general use today The significance of the new machine lies not in its size or capacity which are modest but in the unusually high speed at which it operates and in new construction techniques designed especially for high frequency operation The fastest digital computer ever built is now in operation at the M I T Lincoln Laboratory in Lexington Massachusetts Known as the FX-1 this new computer is in every I It is the first machine with a main memory using thin magnetic films in place of ferrite cores for high-speed random-access storage X I Ampnigned to bo a complete general-purpose small-scale computer for realistic testa of fast logie circuitry and magnetic film storage In system operation Srate In specifying the speed of a computer are two items of particular interest I thethere time required to read a computer word out of the m mor and to write in a new word the read-write cycle time and 2 the speed of the 1oi circuits which may be specified by the of the timing pulses which govern operation of these circuits the clock rate theBoth of these items are noteworthy in the FX- 1 since in both instances the new machine is substantlally faster than the most advanced commercial computers of today Memory The read-write cycle time the central memory of the Linroln FX -1 is for 0 3 microsecond The fastest main memories in machines today have cycle times that generally range from 2 to 12 microseconds These memorise use magnetic cores for storage following techniques developed by Lincoln Laboratory some years ago without which the large high speed general-purpose computers of today could not have been developed The largest core memory in existence with a capacity of more than 2 500 000 bits was built by Lincoln some four years ago and Is part of the older Lincoln TX-2 computer This large core memory has a read-write cycle time of 6 5 microseconds Also a part of TX-2 is a small fast memory using thin magnetic films the first such memory to be installed in a computer In regular use for almost two years this magnetic rilm memory operates in TX-2 with a cycle time of 0 8microsecond consistent with its functions in the computer itself in bench tests a cycle time of 0 4 microsecond was attained limited by the performance of the transistors that were vailable at the time the memory was built The faster magnetic film main In the new FX-l profits from improvedmemory transistors circuitry and fabrication techniques that have been developed in the intervening two-year period Various arrays of magnetic film memory elements deposited on thin glass plates are possible Circular spots were used in the small TX-2 memory and small rectangular spots are used in FX-I The initial FX-1 memory has capacity of 256 words of thirteen bits each buta provision 2 has been made to increase the initial capacity by a factor of four This memory is large enotuch to eerva tho mi- eFv I a realistic on testa of techniques fabrication practical andand scale operating at the same time to provide sufftloent storage to enable the machine itself to be useful for some practical purposes Because of the high speed of the logic circuits and the short cycle time of the merncry the FX -I can match the performance of consider-ably larger conventional machines The memory employs printed-circuit wir ing on a flexible sheet of resin-impregnated glass-fiber cloth The arrays of memory elements deposited on thin glass backing plates are positioned on the wiring so that each magnetic-film element rests on the intersection of two perpendicular leads on the wiring sheet When all the memory element arrays are in place on the lower half of the wiring sheet the upper half is folded over to make the completed memory This single unit contains the 256word 3328-bit memory of the FX-1 computer Circuits The logic circuits In Lincoln's new FX I operate at an effective clock rate of 50 million pulses per second ten times faster than TX-2 and other large machines currently In operation and four times the rate of the fastest comnmercial machine disclosed to date This increase in speed is made possible by high-speed switching transistors developed under subcontract with the collaboration of Lineoln's Cornputer Components Group and now in commercial production The fastest commercial machines now in common use have clock rates comparable to that of the TX-2 Approximately 3000 transistors are used in the FX-1 this is about the same number as in the Lincoln TX-0 computer built about years ago which was the same forerunner five the TX-2 computer in use at the Laboratoryoftoday TX-m has some 30 000 transistors in the central machine and one of the large new coa mercial machines will have as many as 200 000 The FX-1 logic circuits are packaged in plug-in units that have been designed for compactness as well as being particularly suited to high frequency operation Components are mounted on or between two printed-circuit boards that are an integral part of the mechanical framework of the plug-in unit The plug-in units are mounted in trays that hold up to 20 units and themselves plug into the computer each frame Plug-in units with closely related functions are located on a common tray to aimplify interconnections I Approximately 325 plug-in units of 12 defensive weapons The realization of such a standardized basic types are used in the FX-I system for continental air defense was the major preuwcupa•iuzm uZ Liaa wi Ia i tury -- irj They are mountea in 24 trays oi i diuiereni types The entire computer with power supits first 8 years of existence The result is the plies occupies only three relay racks S System SAGE Semi-Automatic Ground Environment tihe largest data-processln system i the trays in the FX-1 are fabricatedSome by a of developmental technique called ever attempted in operational use by Air Force Thisnow system employs some 70the large digital computers designated AN FSQ-7 and a printed-circuit' wiring for the plug-in units and conventional point-to-point soldered wiring for most of the trays The plated-circuit trays employ two layers of etched wiring sandwiched on either side of a central copper groundplane Wiring of this type behaves like strip transmission line with uniform impedance much larger number of specialized data processore All this equipment was originally designed at Lincoln Laboratory with further engineering development and production carried out by various manufacturing contractors Soon after Lincoln Laboratory was characteristics that should simplify and improve circuit performance at high frequencies Interconnections from one layer of wiring to another are made by plated-through holes rather than by soldering The FX-1 is a good vehicle in which to test this type of wiring where it is an important factor in the performance of high-frequency circuits founded the M I T Digital Computer Laboratory became the Digital Computer Division of Lincoln and Lincoln assumed primary responsibility for the use and further development of Whirlwind I In 1953-54 Whirlwind was a primary test vehicle for tho first 1024-word ferrite core memory developed to supplant the electrostatic storage tubes previously employed for high-speed storage The ferrite core memory is an M I T contribution thae has proved to be of fundamental importance to modern digital computer technology The first core memory in Whirlwind had a capacity of 1024 16-bit words with a read-write cycle time of 10 microseconds plated- circuit' wiring as contrasted with The FX-l computer was designed and built by the Digital Computers Group in the Information Processing Division of the M LT Lincoln Laboratory with assistance from Lincoln's Computer Components Group Lincoln Laboratory is a center for research operated under Air Force contract by M I T with the joint support of the U S Army Navy and Air Force Also in 1953 the Memory Test Computer MTC was placed in operation both as a memory test vehicle and as a general-purpose computer in its own right In 1954 a 40906-word core memory was installed in MTC with a readwrite cycle time of about 5 microseconds twice as fast as thi central core memory in Whirlwind COMPUTER DEVELOPMENTLINCOLN LABORATORY MASSACHUSETTS INSTITUTE OF TECHNOLOGY LEXINGTON 73 MASS The Lincoln TX-0 computer was put into operation in 1956 This was the first Lincoln computer in which transistors about 3000 completely supplanted vacuum tubes in the logic circuits It has a 5-megapulee clock rate two and a half time 3 faster than that of Whirlwind or MTC TX-0 served as a test bed for evaluation and development of transistor circuitry and of the largest core memory ever built with a capacity of about 2 5 million bits and a cycle time of 6 5 microseconds This memory was developed and built by Lincoln as a prototype for large memory units produced by IBM for the SAGE System At the time there were no transistors that could supply the currents necessary to drive this core memory hence this memory is vacuum-tube driven and uses about 1000 tubes Computer development at the M I T Lincoln Laboratory had its origin in the M I T Digital Computer aboratory that grew up around Whirlwind I the first modern highspeed general-purpose digital computer Planning for Whirlwind began in 1946 and the machine was put into full-scale operation late in 1951 as the largest and fastest digital computer in existence at that time The design and construction was sponsored by the Office of Naval Research Lincoln Laboratory was founded in 1951 at the request of the Army Navy and Air Force to effect urgently needed improvements in air defense The rapid evolution of computer technology during the period 1946-1951 stimulated to a considerable degree by the development of Whirlwind made it possible to demonstrate the feasibility of a semi-automatic system to process radar data generate displays and guide Direct successor to TX-0 is the larger TX-2 computer Completed in 1958 and still in active use the TX-2 has about 30 000 transistors in the central machine Both TX-0 and 3 TX-2 use the same general circuit design and been concerned with the development of the new operate at the same clock rate 5 megapulses FX-1 computer per second The iarge core memory is now the main Throughout the years of its computer dem emoargeofcor meor smar axliy velopment Lincoln has consistently supported memory of TX-2 but two smaller auxiliary and stimulated the development of higher frememories are also worthy of note In 1959 ai quency transistors through subcontracts with transistor-driven core memory TDCM was transistor manufacturers Several generations put into operation with a capacity of 150 000 bits 4090 36-bit words and a cycle time of 4 5 of transitors developed under th5i program now and In general microseconds In that same year a small mem- N293 are It was thecommonly 2N240 andavailabletransistors that use cry using thin magnetic films was installed in TX-2 the first such memory to be used in an made the TX-a and TX-z computers uol t very fast and it possible is for the 2N769 has now been used at L incoln almost that two years thai Ihv made this knagnetic film memory has a capacity of only 320 bits however it operates with a cycle time of 0 8 microsecond in TX-2 and has been bench tested to 0 4 microsecond No mention Is made here of the many other digital computers and information processing It was at the beginning of 1959 that the systems that have been built for special purSAGE-oriented parts of Lincoln's computer poses by various groups In the Laboratory The work were transferred to the newly-formed discussion has been restricted to a selected few MITRE Corporation The advanced computer general-purpose machines in order to illustrate development groups remaining at Lincoln were the chronologirial increase in speed and capaincorporated into the newly established Inforbility of memories and logic circuitry Tables mation Processing Division with which they are I to III summaviie this evolution in greater depresently affiliated It ti these groups that have tail from different aspects Table I Random-Access Memories in Lincoln Laboratory Computers Year Machine 1953 1954 1956 1958 1959 1959 Whirlwind I MTV TX-u TX-2 TX-2 TDCM TX-2 1961 FX-I Table 11 Type ferrite ferrite ferrite ferrite ferrite core core core core core Read-Write Bits Cycle Time microseconds 16 000 65 000 1 250 000 2 500 000 150 000 10 5 6 5 6 5 4 5 320 0 8 magnetic film magnetic film 3 300 0 3 Effective Clock Rates of Lincoln Laboratory Computers Year Machine 1950 1953 1956 1958 1961 Whirlwind I MTC TX'O TX-2 FX-I Number of Cathodes or Transistors in Central Machine 5 000 5 000 3 000 30 000 3 0O0 4 C C T T T Effective Clock Rate megapulses sec 2 2 5 5 50 Table I11 Representative Operating Characteristics of Three Lincoln Laboratory Computers 1 Ik r I Characteristic 1949-53 Basic word length bits Effective clock rate megapulses per second Speed average operations per second Memory Core bits ReRd-write cycle time microseconds Magnetic film bits Read-write cycle time microseconds Components Cathodes Transistors 1 Irx-i ry 2 1958 -4 2 5 50 30 000 120 000 2 000 000 16 000 2 500 000 0 10 0 6 5 320 3 300 - 0 8 0 3 5 000 0 1 000 30 000 0 3 000 150 20 5 AN UYK-1-A NEW S rANDARD NAVY COMPUTER-THOMPSON RAMO WOOLDRIDGE CANOGA PARK CALIF 1 1961 1636 Power kilowatts - structions with which to set up any desired problem-oriented macro instruction language The AN UYK-1 conveniently operates in multiple word lengths and can perform flonting point operations A fully militarized medium-scale core memory digital computer the AN UYK-1 is now in operation at several Navy field installations and is available off-the-shelf from the manufacturer Stored logic an advanced concept in cornputer logical design was used in the AN UYK-I to achieve a degree of versatility and operator convenience not ordinarily found in such an inexpensive computer Stored logic permits the user to select a word length order structure and instruction repertoire especially suited to the problem at hand These normally wired in characteristics are specified by data stored in the computer's memory and may be changed during the normal loading procedures without hardware modification Stored logic also permite a computer to be designed with a minimun of components thereby greatly increasing reliability and reducing cost The AN UYK-1 was developed under the sponsorship of the Bureau of Ships The objective of the program carried out by Thompson Ramo Wooldridge Inc RW Division was to develop an inexpensive economical-to-use digital computer for general shipboard use The syetern was required to be compatible in word length and input-output characteristics with the NTDS f 5 n and with NTDS peripheral devices The t AN UYK-I was delivered and accepted by BuShips in the fall of 1961 The cornputer has been selected for the TRANSIT high accuracy navigational system and has also been ordered for other military applications by both the Navy and Air Force The new cornputer is particularly well qualified for real time data processing applications in remote locations or in adverse environments where exceptional reliability is required over long periods What stored logic means to users is that they have at their command a computer intentionally designed for efficient operation in the interpretive mode By contrast conventional computers are primarily designed for a particular class of problems and can be adaptedvia interpretive routines-to new classes of problems only at the cost of severe penalties in efficiency caused by the overhead' machine operations associated with conventional inter pretive routines To prepare an operational program for the AN UYK-1 the programmer writes calling sequences as though he were The AN UYK-1 has a basic 8192 15-bit word random access core memory expandable to 32 768 words There are over 8000 useful in5 ------------------------------- T A writing symbolic instructions for another machine There are no efficiency penalties for this convenience because instructions are alwayn av ute _a at machine speeds The following are representative AN UWYT -1 space vehicles surface and subsurface vessels and the testing of flight dynamics execution times tractor wag established for the purpose of Function Double Precision 30 bits Inle Precision 15 bits S many Sq•uare root 1 7 milliseconds 0 83 milliseconds Sine-or cosine 3 9 milliseconds 0 90 milliseconds rctangeni 2 5 milliseconds 0 94 milliseconds Arcsine 56 0 illLfiecods i I5 milliseconds The AN UYK-1 communicates with standard peripheral devices in 15-bit parallel words over one X O channel and with NTDS devices in 30-bit parallel words over two other I 0 channels The computer can receive information from one device while transmitting information to another device A system of 11 interrupt lines provides capability for the time sharing of peripheral devices to connect to and communicate efficiently with the AN UYK-1 The AN UYK-1 is 59 inches high about 20 inches wide and 16 inches deep It is housed in a rugged protective aluminum casting that absorbs shock and vibration and resist corrosion The AN UYK- I ts completely designed to military specifications All ci•cuits are solid state and preferred military components are used An extensive system of stsadard peripheral devices and a growing library of user programs are available to the Navy user UDOFTT MODIFICATIONS-U S NAVAL TRAINING DEVICE CENTER PORT WASHINOTON N Y The Universal Digital Operational Flight Trainer Tool UDOFTT at the Naval Training Device Center Garden City New York is being modified to accept as input data being supplied by a simulated submarine ship control console developed by Electric Boat Division General Dynamics Corporation under the ONB SUBIC program The UDOFTT computer see DCN April 1960 and January 1958 is a high-speed general purpose digital computer with the added flexibility of real-time input-output channels The system incorporated two aircraft cockpits which are activated by the computer The prime objective of the UDOFTT program was to develop a digital computer for real-time control of operational flight traine s Due to its flexible input-output system UDOFTT is especially adaptable to such functions as the simulation of The SUBIC Submarine Integrated Control program for which the Electric Boat Division of Oonnral Dynamics Corporation in prime con- achieving an integration of the information and control function within the submarine The SUBIC program envisions a submarine control room wherein central control of the ship and its functions would be exercised from a minimum of operator stations The SUBIC control room will be constructed to simulate that of either an ASW or an FBM submarine For the FBM version there will be a maximum of seven stations designated ship control surveillance navigation tactical weapons strategic weapons central monitoring and command stations The ASW version will consist of a maximum of six operations stations tentatively called the ship control surveillance navigation tactical weapons central monitors and command stations The 7DM control room can by making inoperative the strategic weapons station and portions of other stations be used for ASW functions It is intended as the initial step in the SUBIC-UDOFTT program to install a functional research version of the SUBIC single operator ship control station for feasibility experimentation A malfunction console will accompany this installation for use in inserting simulated casualties into the various systems controlled at the ship control console The malfunction console will also be used for monitoring performance of the ship control console operator It is not feasible to simulate all seven SUBIC stations at once because of the number of input-output channels and the size of the memory required The UDOFTT will be programmed to simulate the complete dynamics of a submarine and one research console at a time will be tied into the system for feasibility demonstration and experimentation The majority of connections between the console complex and the computer are made through the patchboard systems The main patchboard allown computer input output lines to be utilized either by the original flight trainer equipment or by other external systems such as the SUBIC consoles An auxiliary patchboard is used to provide access to the computer lines coming from the main patchboard for either of two external systems It is thus possible by patchboard switching and change of computer program alone to share the computer for three functions In addition external' systems attached to the output of the auxiliary patchboard can be removed and replaced by Fi others throuah screw-twne connections at the output terminal box of this patchboard system NAVAL TACTICAL DATA SYSTEMSUNIVAC DIV SPERRY RAND CURP ST PAUL MINN The Univac Military Department systems design contractor for the Naval Tactical Data System has been awarded a letter contract for With the patchboard systems described access to the UDOFTT computer is obtained through mamxlmum liability of $19 million for the proof additional equipment The Navy Buof Ships said the contract Is for production of computers and peripheral equipments for NTDS shipboard installations The contract also covers software services such as computer programming installation checkout and continuation engineering according to the Navy Analoee InputCnnels oduction Analog Output hinnes oreau Analog Output Lines Discrete Output Lines Reference Voltage Lines for Analog Outputs 4 Systems Intercommunicaton Lines 2 Systems Interlock Lines 24 4 64 24 16 The Univac AN USQ-gn computer heart of NTDS is the principal development in the program This general purpose stored program real-time machine is severely reduced in else for shipboard use and encased in a rugged cabinet to withstand the effects of shock vibration and salt air Connection has also been made to 20 bits of a computer output register normally intended to feed a printer The UDOFTT computer print register has been augmented with transistorized buffer circuitry to allow the use of the print register for the SUBIC simulation program The output of the register is used o drive digital buffer circaitry which supplies Information to console indiL-ator circuits control pulses for indicator selectiorn circuits timing pulses for a counter and reset pulses The lines from the print register buffer circuitry bypass both patchboard systems and lead directly to the circuits controlled by the signals from this register As systems design contractor for NTDS Univac has been responsible not only for the design development and production of the AN USQ-20 and at least 20 pieces of communicating peripheral devices but also the initial study to determine the feasibility of automated processing of tactical information in a naval combat situation The company also has functioned as coordinator between the Bureau of Ships and other prime contractors and government agencies The latter include the Navy Electronics Laboratory and Fleet Anti-Air Warfare Training Center at San Diego Calif where Univac maintains a permanent consignment of 145 people and a group of naval officers assigned to NTDS For communication purposes the malfunction console has a speaker-microphone a press-to-talk foot pedal and a control switch The switch can be used to turn all communications off to permit communications between the SUBIC consoles only between the malfunction console and the computer console only or among the three consoles Seventeen AN USQ-20 computers have been delivered to the Navy Nine are already installed and operating aboard ships of the fleet Mitary counterpart of the AN U5Q-20 is the Univac 1206 military computer two of which A similar attack in being planned for the SURIC Surface Integrated Control program The SURIC program is concerned with the development of new concepts to facilitate the control by command of all functions of a surface ship This program Is being developed by Sperry Gyroscope Company under ONR sponsorship The first console to be installed and evaluated will be the conning console which is designed to increase the performance of conning officers in vehicular control of the ship decision making in navigation maneuvering and collision situation and communication with Internal and external stations have been delivered to non-Navy customers The 33 x 3I x 6p-ckgh computer contains 3776 identically packaged circuit modules Rollout drawers permit easy rapid access to the component packages Its very high-speed random access memory contains one million bits of information Thirty bits comprising a single word may be extracted from any location in the memory in only 2 5 microseconds The computer io capable of completing an instruction in 13 microseconds or 77 000 instructions in a single second The SURIC-UDOFTT pr gram Is in the planning stage and integration plans between console and computer are not complete Plans are underway to utilize the SUBIC Electric Boat external interface equipment 7 An expansive array of electronic data gathering devices and communicating equipments combine with the computers to form a shipboard NTDS complex Input trackinal in formation received from external sensor devices-i e sonar and radar-are used by the computers for target evaluation identification of threats determination of what types of counter weapons to employ and assignment of weapons The latter might include guns missiles or intereept aircraft information retrieval However it is anticipated that time on the computer will be available for University research and student training Computers which can collect store and evaluate tactical information and make decisions perform these functions in a small fraction of the time required for conventional systems to accomplish the job At present some 3-1 2-million cards comprising approximately 80 000 articles in the field of metallurgy are being transcribed to magnetic tape These include much of the journal literature from 1958 to date More than half of this file has already been transcribed Inquiries to these files compose retrospective searches Current awareness searches are being conducted now on a weekly basis The retrospective searches will begin as soon as the transcription is completed With the computer General Electric Cornpany also delivered a program to perform the literpture searcehing which was previously done by the Western Reserve University Searching Selector a relay Searching Selector which was designed and constructed at Western Reserve University An automated Navy Combat Intelligence Center CIC enables the units in a task force to operate as though they were one huge ship GE 225 AND INFORMATION RETRIEVALWESTERN RESERVE UNIVERSITY CLEVELAND 6 OHIO The 8192 word core memory with 2 tape units and punched cards in and out makes a nice configuration for much of the University research as well as student training An assembly routine known as GAP is now being used for programming the GE 225 A compiler which is in preparation at the General Electric Cornpany Phoenix Arizona will also be available The Center for Documentation and Cornmunication Research in the School of Library Science at Western Reserve University installed a GE 225 during the summer of 1951 Its main purpose is to perform literature searching and COMPUTING CENTERS of the down-time in the early months was due to inexperience of maintenance personnel in servicing the memory The Daystrom memory is one of the largest and fastest all solid-state memories in use today It has a storage capability of 20 000 words each word 60 bits in length and a full read-write cycle of 8 microseconds It contains many design features including transistorized switching circuits which allow the unit to work as part of the NORC systern in the same mode as the original vacuum tube and totally different type of memory which it replaced One of the original large high-speed digital computers NORC occupies some 3500 square feet of floor space at the Naval Weapons Laboratory Dahlgren Va It has been in almost NORC MEMORY PERFORMANCE-DAYSTROM INC ARCHBALD PA In March 1960 the Navy updated its large Naval Ordnance Research Computer NORC which recently tracked the Soviet cosmonauts by installing a solid-state random access core memory as a replacement for the computer's original CRT memory unit A recent performance report from the Navy on the replacesent memory indicates that it has more than lived up to all expectations It has greatly improved computer reliability and reduced overall computer down-time The report states that for a total operating the period March time of 12 407 hours duringtime between failures 1960 to August 1961 mean constant operation since 1955 and can accomplish 15 000 three-address arithmetic operations per second attributed to the memory has been better than 1770 hours During the same 18-month period it established a down-time to total-operatingtime ratio of better than 0 3 percent During the last 6 months of operation the ratio was better than 0 1 percent It should be noted that much In recent months in addition to so-called routine work NORC definitely established 8 that Soviet cosmonauts Titov and Gagarin were in actual orbit around the earth It also tracked their orbital flights and kept the world informed of their progress as they circled the globe NORC also has handled other highly complicated assignments including guidance calculations for Polaris missiles and surveillance satellites plus dozens of other highly clammifled projects of computer techniques in traffic engineering by setting up a computer model of two north-south and two east-wast streets both two-lane and two-way All four intersections were signalcontrolled and the route straight through right turn or left turn for each car was randomly assigned at each intersection Each car was identical to all others and was represented by one binary digit or bit all moved at the same speed and maintained the same spacing between cars Traffic flow in the Goode model was presented in motion picturei form for analysis CMU RIUAO COMPUTER SIMULATION OF CITY TRAFFIC-NATIONAL BUREAU OF STANDARDS WASHINGTON 25 D C The National Bureau of Standards has programmed high-speed data processing and display equipment to simulate traffic flow over a nine-block length of a principal traffic artery in downtown Washington D C After information on volume of traffic and traffic controls has been fed Into the system the simulated traffic flow is tabulated on printouts and is also shown in a motion picture of simulated cars moving changing lanes and stopping for lights as in a helicopter view of the actual streets This result has been attained in a three-year program conducted by M C Stark of the NBS Data Processing Systems Laboratory for the Bureau of Public Roads Configuration of Model In 1958 the Bureau of Public Roads requested the National Bureau of Standards to conduct a traffic research study by means of a aimulation model using several improvements over the earlier work as suggested by Professor Goods The most significant improvement was the use of a computer word to permit the use of more variables and a planned route for each car instead of tabulating it am an undistinguished computer bit The model selected for use was based on a heavily traveled 0 8-mile stretch of Washington D C 's 13th Street N W which includes ten Intersections from Euclid Street to Monroe Street Seven of the intersections had traffic signals and three were controlled by stop signs at the east-west streets The model includes several two-way cross streets two at a 60degree angle one T-intersection and several one-way cross streets The study was restricted to the peak evening rush configuration in which all four lanes of 13th treet are used for northbound traffic For some time the rapid increase of traffic on city streets has been a source of concern to traffic engineers and city planners Municipalities must assume that streets now used to near capacity will have to carry even more traffic in the future Thus traffic experts feel that detailed studies to correct congestion points which even now are urgently needed may become absolutely essential within perhaps the next decade In such studies the problem is to determine the results of proposed changes in traffic control measures without actually disrupting traffic Automatic data processing to determine the optimum use timing and placement of traffic control devices appears to offer a promising approach to this problem Simulation runs can be made with a computer to study the sensitivity of the traffic flow to proposed changes in the signal system and to explore the capacity of an existing system to handle different patterns or increased volumes of traffic Many other traffic engineering situations such as use of one-way streets banning left turns location of bus stops and restriction of parking also can be studied in this way Previously acquired traffic-uurvey information was used to determine the volume of cars traversing the entire course on 13th Street and those entering crossing and leaving it at each Intermediate point This permitted the computer program to show traffic composed of purposefully operated vehicles each having a route assigned at the time of its generation The streets of the model were divided up into 12-foot long rectangles called unit blocks The unit blocks in each lane were numbered in sequence from entrance to exit of the course and cross-wise at each side street so that any position could be given by unit block number The computer required the position of each vehicle for each computation and assigned a new position if changed as part of each computation Previous Work In 1956 H H Goode of the University of Michigan and his colleagues reported the use 9 -- I permitted the desired speed to be attained The overtaking car was switched to the lano nelected by being moved through progressive intermediate straddle positions during the time required to make the change Vehicles obliged to stay in the same lane were gradually decelerated to the speed of the leading vehicle Operation of Model Vehicles of the model were generated at each of the poosible entrances to the course by means of random number generators in proportion to their numbers in the real course At the same time each vehicle was assigned characteristics determining its route and behavior in traffic also by means of random number generation and in numbers corresponding to the proportions in actual traffic Most vehicles used 13th Street as an artery being generated below the simulated stretch and leaving it at its northern end Each vehicle destined for the end of the course continued at its desired speed unless forced to reduce speed for traffic signals and slower traffic in the same lane each continued in its original lane unless forced to change to avoid being slowed by overtaken yehicles The routes assigned to vehicles at the time of generation determined their behavior in complex intersection situations Westbound vehicles were not permitted to turn left 13th Street being one-way northbound and hence could always proceed through or make a right turn in the lane determined by route or lane preference assigned at time of generation Eastbound yehicles assigned a turn onto 13th Street were obliged to await a gap in westbound traffic Those requiring a near or far lane because of a later turn waited to enter 13th Street on the appropriate lane Those not assigned a later turn entered on the preferred lane 1 or 4 except for vehicles having a LANE 4 preference which if blocked by oncoming traffic went on to enter at LANE 1 waiting there to turn if necessary The vehicles generated at each entrance to the model were described by two words in digital format Caracteristics determined at launch time included Time of departure in 1 4secorm latervals type of vehicle--automobile small truck or large truck exitPont to be used in det ermining the route and desired speed categor--15 20 25 30 or 35 mph All of these characteristics were chosen by meanJi of random number selection from a series proportioned according to empirical knowledge Vehicles assigned a turn off of 13th Street were coaxed into the appropriate lanes when within 1200 feet 100 unit blocks of the turn A definite pattern of last chance unilt blocks for each lane shift approaching each intersection was programmed into the computer The cars made the necessary shifts in as rapid succession as possible when approaching the turning point following the lane-switching rules Additional information was added within the vehicle two-word format as the computer surveyed the entire course at 1 4-second real-time intervals Its computations determined for each vehicle the length of Its Jump or distance traversed during an interval and assigned to each its new actual speed and position given by its unit block number and the hundredths of the block length to which the vehicle's nose had penetrated Computer Operation Vehicles approaching stopped vehicles in the same lane where lane changing was not possible a stop sign or a red light were decelerated gradually this took the form of 1 4second jumps of decreasing size A stopped vehicle was identified by its two-word digital description showing a zero jump ndindicating the same position at successive intervals The computer operation was performed by first programming the rules of the road Into a high-speed computer and filling the model course with vehicles in a preproduction run Several computer runs each of three ccmplete 80-second traffic light cycles four minutes were made Sixty minutes of computer tim6 was needed to process each run because of the many computations required-as many as 500 in the complex lane-changing situation -for more than a hundred vehicles each 1 4 second A magnetic-tape recording of the hiimula- When the distance between any two vehicles in the same lane became less than the allowable net clear sight distance determined by the speed of both vehicles the net clear sight distances for the overtaking vehicle in the two neighboring lanes were determined as part of the computations of each 1 4-second interval The three alternatives stay in lane switch to right or switch to left were evaluated at each interval and the one chosen was the one which best tion and four tabular printouts were obtained from the computer all were used in later aitalyseis One of the printouts the VEHICLE GENERATION TABLE gives for each vehicle the launch time the exit the type of vehicle car truck 1 truck 2 or marked vehicle the generating point the desired speed and the lane preference Another printout the STATION B CHECK tabulates vehicles passing the maximumload point of the course for comparison 10 I I AEC COsMPU1tui ArnJ AP'i JJI MATHEMATICS CENTER-NEW YORK dLg Thie Lhird prinouui ihe wislarili VEHICLE RETIREMENT TABLE tabulates the WitI ItN1YiFJITY NEW YORK N Y individual running times and actual speed of vehicles completing the course in each lane also for comparison with empirical data Finally the MARKED CAR CHRONOLOGICAL PRINT- An IBM 7090 ham replaced the IBM 704 at this center and the present peripheral equip- OUT gives the location of each marked car every 1 4 second for analysis of its progress ment will be replaced by an IBM 1401 The 7090 has 32 K Storagre The magnetic tape obtained from the corn- 2 Data Channels 7 Index Registers 12 729-IV Tape Units As many as 4 of these can be connected to the 1401 Card Reader Card Punch Printer puter was used to make a motion picture film of the simulated model in operation resembling a helicopter view of traffic flow on the course The tape supplied the input to the Bureau's SEAC computer which operated an oscilloscope to produce a visual presentation of the computed vehicle movements This presentation was retained for repetition and analysis by triggering a 16-mm motion picture camera mounted in front of the oscilloscope for four frames to depict the situation at the completion of each 1 4-second real-time computation The processed film when projected at 16 frames per second shows the simulated traffic movement in the model for the 4-minute run in real time Furthermore the 7090 has 2 new instructions Enter Significant Mode ESM and Test whether in Significance Mode TSM The latter also causes the machine to leave the significance mode of operation If an ESM ham been executed the results of floating point operations will be numbers in standard floating point representation but with Just enough leading zeroes in the fractional part so that all the remaining bits are significant If an ESM has not been executed the 7090 will do floating point operations in its usual manner Analysis of Results Analysis of the tabular data and the film showed that the computer program caused the vehicles to behave in what seems to be a very realistic manner They stopped at red lights yielded right of way at stop signs moved at various speeds maneuvered for turns and to overtake slower cars and formed queues when necessary in short they did most of the definable things that are done by real cars in city traffic During runs of the model vehicles actually came to a stop if they reached the last chance position without making the lane shift just as seen occasionally in real traffic COMPUTER TRAFFIC CONTRO --TRW COMPUTERS CO CANOGA PARK CALIF A digital computer system will be used to help control vehicular traffic in Los Angeles this spring From a control center in City Hall the computer system will monitor 4 miles of Sunset Boulevard west from downtown Los Angeles and regulate traffic signals in response to vehicular flow The simulation technique has produced a model which apparently can be made to correspond reasonably well with actual field situations Thorough evaluation of the model will require new field data as traffic on 13th Street has changed considerably since the original counts were made When validated this technique will be useful in predicting the detailed effects on traffic flow due to changed parameteor-moved or removed bus stops altered signal light timing and the like Computer simulation will make possible experimental manipulation of traffic situations without the possibility of snarling the real traffic Most important experimental manipulation of traffic loads in models of today's streets should make it possible to estimate how long these streets can be used without change and to predict what changes will then be needed The computer a Thompson Ramo Wooldridge RW-300 is capable of analyzing and directing traffic patterns and reacting in stantaneously to changing traffic conditions on the crowded boulevard This pilot system which will mara the nation's first use of a digital computer by a city for traffic signal control will be gradually expanded to control more and more of the critical intersections in congested areas of Los Angeles The installation of this computer system will help speed the day when traffic control in Los Angeles will be able to keep pace with the ever-increasing volume of vehicles on the city's thoroughfares Thir joint effort of the City Traffic Department and the traffic control experts of Thompson Ramo Wooldrldge is another 11 i Fi step in the overall Los Angeles redevelopment plan becoming the first city in the nation to take this naralla lamr•l h u4no a ell-4- f arl By locating the control center in City Hall The computer will receive traffic volume tiand movement information transmitted by icl- the City Traffic Enmineer will be ble to super- phone lines from automatic detectors located within and at the borders of the controlled seetics of Sunst Bolevard By usin this data and an analysis program stored in its memory the computer will continuously decide on the best settingi of the traffic signals These docistons transmitted back to the intersections will control the signals to provide the most effective flow of traffic vise traffic movement more effectively and maintenance of the manter' control equipment will be made highly efficient By makin traffic signal control reoponsive to traffic needs Los Angeles is attempting to utilize its street syn tern to the greatest efficiency thus increasing street system vehicular capacity establishing a high level of service to motorists reducing vehicular operating costs and improving the safety of vehicular travel By utilizing the experience gathered on the traffic flow from this 1 percent of the city's intersections future traffic problems can be accurately anticipated and computer control may be readily expanded to meet these forthcoming needs Basically the system will regulate traffic flow by controlling lights relative to traffic voluie For a single light such control would be relatively simple Vehicle sensors in the four streets that meet in an intersection could be used to actuate a master controller that would regulate light cycles in response to the number of vehicles detected One type is the treadletype vehicle detectors that are often used on side streets and sometimes on all four streets at an intersection These detectors are used as inputs to vary the basic fixed cycles of the lights at the intersection The high speed of the RW-300 computer and the ease with which it can communicate with the signal lights at a great many remote points allows the computer to be extremely adaptable to analyzs- and alleviating some of the complex traffic problems of Los Angeles The downtown area of Sunset Boulevard chosen for the initial application of computer contr6l is not only a major thoroughfare but is also an important bypass for a heavily traveled section of the Hollywood Freeway Furthermore Sunset Boulevard experiences a variety of peak flow traffic patterns as a result of many downtown special events For a number of lights however such single intersection control has little relation to the overall traffic pattern To control this traffic pattern most efficiently each light must be controlled in a way that is responsive to the entire traffic flow For this control to be efficient a central system that senses the traffic volume at a large number of points and controls the signals in response to that mass traffic flow must be utilized Sumset Boulevard is a major thoroughfare in its own right In the central city it lies substantially parallel to the Hollywood Freeway With the computer control system Sunset Boulevard can be developed as a highly effective signalized thoroughfare to relieve the Hollywood Freeway and to serve as an emcwgency route when the freeway is closed for any reason The TRW system to be installed on Sunset Boulevard will combine the best features of both traffic control systems described That is each of the controlled intermections will have its own local controller this controller will time clearance intervals pedestrian walk intervals and other fixed-length intervals The computer in turn will control the green intervals at each intersection informing the local controller when to establish the cycle split and offset appropriate to existing conditions in the overall traffic pattern Thus one objective of the new signal control system on Sunset is the development of major thoroughfare capability Another otJective of the Sunset Boulevard installation in to raise It to the standards set for major thoroughfares In Los Angeles Two principal policies are considered by cities when they modernize their traffic control systems 1 io provide a centralized control system and 2 to provide a system responsive to traffic needs Some cities have adopted one of these objectives some the other The City of Los Angeles in its traffic modernizsaton program of which this Sunset B Alevard pilot installation is a part has adopted both thereby Twenty-six signal lights along Sunset from Alameda to Hoover Boulevard and 10 lights on approach streets will be controlled initially by the computer system Two of the intersections to be controlled are three-phase intersections At a number of locations detectors will count the traffic entering the controlled section 12 I of Sunset Boulevard and at important locations h4 h of mnaaf a a a athletic events can also be handled by the com 6 SuAe AU sJAV0 %h u--------------AIAWU aI JawaUI in its operation with daily traffic the computer's stored program can be prepared to handle the abnormal traffic flow in the optimum manner system will include pressure-type vehicle detectors and electronic detectors These counts will be transmitted by leased telephone lines to the RW-300 digital control computer at the control center in City Hall T o e a u o t sTRW SThe computer making use of established control techniques and techniques that will be developed in future as a result of this and other research will compute the appropriate signal timing for the traffic signals on Sunsat Bouleyard This timing information will then be transmitted to the traffic signals will prepare the Initial computer program and train city personnel in its use The computer system will have unused memory capacity that can accommodate traffic signals at many additional intersections at other locations within the city This extra capacity could alternatively be used to control traffic on the nearby freeways by controlling the access roads to the freeways Side street detectors will be employed at several locations to detect the arrival of traffic from side streets into and through the system For several years TRW has been especially interested in the development of systems for the solution of traffic problems For some time now it has had an Automobile Traffic Control Section working full time on studies and the application of digital computers to this ever-increasing problem The personnel within the section have blended an advanced knowledge of computer technology with many years of experience in traffic control Control circuits at each intersection will time clearance intervals pedestrial walk intervale and other fixed-length intervals These controllers will also have the capability for carrying out fixed-cycle operation The computer will control the green intervals at each intersection establishing the cycle split and offset appropriate to existing condIT-ons Cyele is the time for one complete change of signals split is the apportionment of cycle time betweie-n-he streets that meet at the intersection offset is the time difference between cycles at successive signal lights The traffic control installation Is the result of a 2-year study conducted jointly by the Los Angeles Department of Traffic and Thompson Ramo Wooldridge Inc The TRW computer to be used has been extensively proved in online control of many chemical plants oil refineries cement plants power generating etations and missile testing facilities The RW-300 computer is a general-purpose magnetic-drum storage stored-program serial machine It is fully transistorized for maximum reliability The computer is modified for traffic applications to provide counters for accumulating data from the system detectors and to provide additional instructions applicable to traffic control This installation is one of three computer traffic control systems engineered by Thompson Ramo Wooldridge An RW-300 computer was previously used by the Federal Aviation Agency for over a year in the study of problems of air traffic control A pair of TRW-330 computers will soon be installed on one of 'he nation's most heavily-traveled thorcr hf tres for control of toll registration The RW-300 digital control computer provides the advantages of exceptional availability in excess of 99 percent in around-the-clock service and high-speed response-hundreds of calculations per second Furthermore any radical changes in traffic or topographical conditions will not obsolete the computer but will merel7 require changes in the computer's program DOES ALL INTERPRETATIVE ROUTINE-U S ARMY CHEMICAL CORPS BIOLOGICAL LABORATORIES FORT DETRICK MD The compu er has the ability to store a wide variety of programs to take care of special situations Thý computer can decide when any of these specialr programs shall become effective basee on criteria established by the traffic enginear For example one or more special programs are expected to be developed for handling unusual weather conditions The unusual traffic patterns that occur during An interpretative routine for the Univac Solid State 90 was written with two objectives in mind First to speed the return of computer service by shortening programming time Second to enable nonprogrammers in need of high-speed computations to write their own programs To free the latter from any attention to decimal placement all calculations are done 13 to sort out and reproduce a list chosen from rtiiiesin a very snort a z-i c' ' a m il ner time in floating point The routine accepts instructions in the form of an 8-digit English mnamnninA its repertoire of 27 instructions includes the common logarithmic exponential and trigonometric functions Current use of the routine indicates the objectives have been met It is estimated that the developm -ni installation and testing of the MEDLARS project will take about 2 years The new building of the National Library of Medicine adjacent to the National Institutes of Health in Bethesda Maryland which will be ready for occupancy late this year will be adapted to incorporate the MEDLARS equipment MEDLARS INFORMATION STORAGE AND RETRIEVAL SYSTEM-U S DEPARTMENT OF HEALTH EDUCATION AND WELFARE Washington 25 D C Public Health Service announced th'ot a contract has been signed with General Electric Company for the development of an electronic information storage and retrieval system at the National Library of Medicine to be known as MEDLARS Medical Literature Analysis and Retrieval System DIGITAL COMPUTER DIVISI N-U S NAVAL ORDNANCE LABORATORY CORONA CALIF The IBM 7070 which has been in operation for 8 months was installed and accepted in January 1961 The system configuration as presently installed is as follows The new computer-based system will enable the National Library of Medicine to broaden and accelerate its services to medical education research and practice The Library which this year observes its 125th anniversary is responsible for acquiring indexing storing and disseminating world literature relating to the medical sciences The Library hae the largest collection of scientific medical literature in the world - 5000 words Core Memory 7 Magnetic Tape Units - 729 Type II - 500-cpm Reader Card Input Card Output - 250-cpm Punch The computer is being used on a single shift basis in performing the Laboratory's scientific and technical data processing workload The 7070 replaced a government-owned Burroughs 205 which for some time had been inadequate to handle the computational requirements of the Laboratory The basic publication of the National Library of Medicine is the Index Medicus a monthly bibliography of world medicine literature which during the past year listed some 125 000 items representing scientific publications of 77 different countries in 30 languages The Library also publishes special bibliographies and conducts an inter-library loan service which has disseminated as many as 11 000 separate articles on request during a single month The Laboratory's computational workload arisos from four principal categories of problems Mfissile Flight Data Processing The processing of photographic and tele'metered missile flight data accounts for 25 percent of the computer's approximately workload Field and flight test data to pr'oc- The MEDLARS system is a pioneering yenlibraryIn pr acto conventional ture relation the tices in There have been other efforts bibliographic field with systems using electronic computers but none approaching the size of this one MEDLARS will be designed to process several hundred thousand pieces of bibliographic information annually eased on missiles during the contractor development stage and continues to be processed au the missile program progresses to final fleet usages Typical data processes are radar boresight camera data photo-theodolite camera data dial box data sampled FM FM and commutated telemetered data Mitchell camera data and drone pod camera data The present system which is part manual and part mechanized is designed to turn out a single product-the Index Medicus In contrast MEDLARS will give the flexibility needed to meet other national requirements It will be possible to produce by machine quickly and efficiently specialized bibliopraphies to meet specific requests If someone asks for a bibliography of publications on a single disease category for example MEDLARS will be able Production and Surveillance Data Processing The processing of production data for the quality assurance program and of surveillance 14 I data on field test Infnrmtflnn Mr tho rheaHl4v _•Pi•n 0A %mne • --- -ecv crt the 7070 from a card-oriented to a tape-oriented system by the addition of an IBM 1401 to the computer faculty and readiness programs accounts for another 40 percent of the Laboratory's workload One of the larger jobs in the Information Storage and Retrieval area involves the up-to-date maintenance of complete and uniform records of all tests made on TERRIER TARTAR TALOS SIDEWINDER SPARROW and BULLPUP mismiies Various periodic reports and special summaries are extracted from the files COMPUTATION CENTER-U S NAVAL WEAPONS LABORATORY DAHLOREN VA The first computer program for PERT Program Evaluation and Review Techniques was written by the Naval Weapons Laboratory and placed in operation in 1958 While the original PERT was intended for monitoring and expediting the Fleet Ballistic Missile pro gram the value to management of the PERT concept has since been widely recognized and applied in Government and industry applications by this laboratory have included EagleMissileer Big Dish and NASA projects The original PERT program for the NORC computer has been frequently revised to increase processing efficiency and usefulness of the output A still more flexible and efficient version for the IBM-7090 was placed in operation June 1981 Present PERT programs deal primarily with time schedules a new program is being planned which also includes cost data In order to provide an effective information storage and retrieval capability the Variable Information Processing VIP System has been implemented on the 7070 This system combines general applicability flexibility unrestricted content and speed in such a way as to provide an extremely versatile and effective information storage and retrieval system VIP is currently being utilized for information on eight missiles which is supplied on thirteen different data collection forms Lethality Analysis The detailed analysis of the effectiveness of warheads against target aircraft under various circumstances of encounter is carried out in support of the Laboratory's fuze development program This lethality analysis work comprises approximately 10 percent of the workload being performed AERODYNAMICS LABORATORY-U S NAVY DAVID TAYLOR MODEL BASIN WASHINGTON 7 D C Miscellaneous Scientific Computation The David Taylor has Model Basin's Aerodynamics Laboratory added a 2nd Alwac III DCN October 1958 for use in its wind see data E scientific miscellaneous The remaining computations are composed of problems of tunnel reduction and research work Abwcmputtioowins areomposedyproblemsence of any definitely superior secondgeneration computers in production for under Computation of band structure and water and carbon dioxide $100 000 was a principal factor in this choice Also the reliability advantage of two Identical computers will more than double the Laboratory's previous computing capacity Of interest also is the recent running of a first production program compiled by ALSAP-1 a compiler written by E Manderfield of Alwac and J E Blalock of the David Taylor Model Basin accepts computer-oriented language and compiles a machine-language floatingpoint program Reduction of spectroscopic data Tables of emissivity measurements Bond strength calculations Prcessing r oALSAP-1 of the sea Missile data handling system simulation 15 q COUPUW S AND CENTES ERSEAS ALGOL 60 COMPILER-FACIT ELECTRONICS AB SOLNA 1 SWEDVN There is obviously a need for more powerfui computers Since there is no point in mak- An Algol compiler the first In Sweden has recently been completed for the FACIT 3DB computer of Facit Electronics AB The language used is Algol 60 except the symbol own and recursive procedures there are alJm some r'estrIctions on variable index bounds for arrays expressions called by name and length of identifiers The present compiler uses only the con tral unit of the FACIT EDB-core storage of 2000 words drum storage of 800 words and Input-output of 5-channel paper tape The programs are written direct in Algol 60 Reference Language with the limitations mentioned above and converted into the appropriate hardware representation by the punch typist The compilation resuts in an effective machine code program and is quite fast A program of 200 declarations and statements takes about 10 minutes to compile about half of this time is used for input of the compiler and output of the object program The compiler had been used and tested for some months before its release on February 1 1062 An extended version using magnetic-tape and external-core storage and with facilities for large-scale data processing is being considered at present possible the Atlas hae been designed to provide the greatest computing power that can be obtained at reasonable cost Making this big technical jump forward Atlas is 100 times faster than Mercury is in fact one of the means by which the reasonable cost is achieved This is because the value for money obtained in computing power rises roughly In proportion to the square of the actual price of the machine-an economic fact of computer manufacture ing a small jump when a big Jump in technically Apart from the advantage qiven by this natural law the low price oi computing on Atlka is also partly due to the gr•eat economy and ingenuity of the techdical design Many of the jobs which in other computers require oxpensive special circuits for example to control associated punched-card machines are dealt with in Atlas by internal programmes obeyed simply by the main control unit of the computer Itself This is an economy made possible by the very high computing speed and full advantage is taken of it in the Atlas design To ensure that maximum utilization of the computLig power is obtained in practice the designers have also exploited modern programming techniques to the full to organize the machine's internal flow of information in a better way The manner in which a computer has to shift large masses of information about at high speeds in many different directions Is rather like a big city in the rush-hour A great deal of organization Is needed to make the system run smoothly and to get the commuters or numbers to their destinations with minimum delay In Atlas this organization is provided by a supervisor programme kept permanently in the machine ATLAS-FERRANTI LTD MANCHESTER AND LONDON ENGLAND The fact that the Atlas see DCN October 1960 is the most powerful computer in the world does not mean that it in a kind of colossus set apart to be approached only for very special purposes The most impressive thing about this machine is the fact that the work exists for it to do its huge capacity for calculation and data processing can already be satinfled Atlas has been built not to break a record but to meet a demand Thus although an Atlas installation costs something in excess of a million pounds to buy it provides the lowest cost per computing operation that ham ever been made available to the user This is the real significance of Atlas being the most powerful computer in the world People not familiar with the computing field may not realize the extent to which existing machines are boing swamped with work As an example one Pegasus computer in the Ferranti Computing Service if allowed could be kept entirely occupied night and day with the work of two or three existing customers In practice Its time is rationed out to a good many more clients Mercury machines the fastest hitherto built in Europe are unable to cope with some of the vast calculations required by the scientific establishments in which they are installed The improvements in organization are not simply rearrangements of existing types of electronic building blocks They have been made possible by radically new techni4ues in electronic circuitry developed by Professor Tom Kilburn and his team at the University of Manchester These techniques take the currently-available electronic componeats and 16 i methods of construction to the very limit of their Atlas to switch available storae space in the ruM1 Is MAuirni way between too various programmes so as to reduce waiting time for tise by the rate at which electrical signals can be transmitted along wires almost the speed of SliFor i spes the system trnsaers a oeaaup diif Atlas can in practice perform about a mtllion simple operations additions for sample block of termation belongiag to Programms 1 fom the drum store to the core stoe the multiplication are performed at about 300 000 per second The machine has a word length of 48 binary digits this can be used fnr fixedpoint numbers 40 digits long for floating point numbers 8 digits for the exponent for alpha numerical data eight 6-bit characters or for programme instructions 10 digits for the function part the rest for various ad- empty to receive back the same block it may well be used by the automatic system to take a different block of information belonging to Pro gramme 2 When the Programme I block is no longer needed for computing it Is then sent back to occupy another space which has become available per second More complex operations like apaWe left on the drum does not have to remain dresses Another feature of the main store which contributes to the oighcomputing speed is a means by which the instructions can be overlapped in time to some extent This is made possible by providing several distinct paths of access to different parts of the high-speed core store A variety of input and output equipment is available including magnetic-tape stores capable of transferring data at 90 000 characters per second By the use of its time-sharing facility a common feature of most modern fast machines the computer will allow transfers of information to take place between itself and up to 20 peripheral units and 8 marnetic-tape units simultaneously An Important feature of the electrotdo design is a special fixed store which holds about 250 internal programmes used for various arithmetic and control operations in fact all the operations normally found in the subroutine library of any well equipped computer These internal programmes are called into action by special extracode instructions written in the main programmes One of the main design Improvements in the Atlas is the method of achieving rapid transfers of information into and out of the high-speed store Physically the main store consists of a high-speed magnetic-core store backed up by magnetic drums of slower access but much larger capacity In orthodox computers transfers of information between the two have to be organi•ed by Instructions written by the programmer but in Atlas the whole job is taken over by a built-in automatic system As a result the programmer does not have to think about two distinct stores but simply works as If there were just one high-speed single-level store of large capacity Another important electronic design feature Is the special circuitry which makes the high arithmetic speed possible Essentially this Io a new tTpe of adding circuit with an extremely fast carry operation It ensures that the carry process is always completed within the very short transfer time of Atlas which is only a fraction of a millionth of a second In common with all modern computers the electronic circuitry of Atlas is constructid from transistors and other semiconducto components and these are mounted on plng-in packages for ease of maintenance Comprehensive test routines held In the fixed store are regularly brought into operation on a time-sharing basis during suitable intervals caused by transfer processes In the main programmes This simplicity of use is achieved by what is called a page address system for the stored numbers and instructions Here the numbers do not have addresses signifying particular physical positions in the stores They are identified simply by being in particular blocks of numbers called pages at particular positions in those blocks These pages themselves have no fixed locations but are moved about according to which page is needed in the high-speed core store for computing operations The automatic system keeps a running record of where the pages are physically so that when a programme calls for a number at a particular address it can always be found With time-sharing operation this system allows the ALGOL-INSTITUT FUR ANOEWANDTE MATHEMATIK JOHANNES OUTEINBERO UNIVERSITXT MAINZ MAINZ GERMANY ALCOR MAINZ 22 the final ALGOL trans later for the Z 22 has been finished and in 17 - tAandlev ALG•i - with some unimportant restrictions DEFENCa NP W E' MW PD RESEARCH ESTABLISHMENT LILLESTR6M NORWAY MALNZ 2002 the ALGOL translator for the Siemeu computer 2002 with 2000 words magnetic-core storage and 10 000 words magnetic-drum storage has been completed and in operation since December 1901 The translator handles ALGOL 80 with minor restrictions ALCOR convention of 11 October 1901 Norwegian Defence Research Establishment Division for Telecommunication Lillestrum Norway is developing a special purpose digital computer for real-time signal procensing It is intended for extraction of weak signals from noise A met of 25 different digital and analog-digital printed circuit modules are used operation since July 1961 The translator IALCOR MISCELLANEOUS FLOATING PUNCH KEYPUNCH-BUREAU OF THE CENSUS WASHWGTON 25 D C method are controlled by the program card and the operator requires no additional instruction A new card punching technique has been developed by the Machine Tabulation Division of the U S Bureau of the Census by modifying an IBM 027 card punching machine Because of the standard field size a standard card form may be designed to fit the requirements of any subject matter to be punched The punch card is now released from the fixed field format by the addition of a two digit code to identify the four column data field This advantage Is greater on data to be recorded on magnetic tape since all of the columns of a card could be filled The information on the tape is now continuous without the blank portions normally found on the fixed field cardto-tape method Since the data fields in the card are the same all data related to one record is punched in sequence and columns of the last card The computer can use this count as a check in determining if all information for a record has been received The computer can also restore the number of digits dropped and round off the floating point number This technique Is called Automatic Floating Point Punching It provides a method of reducing the number of digito required to express a number in a punch card The machine automatically punches the first three significant digits into the first three columns of a field and a count of the remaining digits into the fourth column The number keyed and the resulting punchIng are as follows Values Punched 7 24 838 4836 0070 0240 6380 4831 1272 6223 4984 5435 12764 022487 4987285 54332960 PLATO II-UNIVERSITY OF ILLINOIS URBANA ILL Introduction PLATO' in the name of a research project in the field of multiple-student machines currently under way at the Coordinated Science Laboratory of the University of Illinois The main aim of the project is to develop an auto matic teaching system sufficiently flexible to permit experimental evaluation of a large vartety u ideas on automatic instruction This 027 keypunch modified to do the floating point punching punches left-hand xeros automatically The verification of this type of punching is done on the same machine and in under program card control This program is based on using an eight digit maximum number and reducing it to a four column field This combination crn be changed to meet other speooficatlons The fields to be punched by this 1 The goal of project PLATO is to be realized by constructing a series of machines each em- PLATO Programmed Logic for Automatic Operations 18 Lam-_ •'iimir necessary Dut routine calculations or it can quickly plot for the student graphs of hIs solutions to equations J by experience - ta with earlier models PLATO U differs from PLATO 1Z primarily in its ability to instruct s number of students concurrently The teacing logic employed in PLATO U resembles that of PLATO I in most essentialm For completeness a resume of this logic is presented in the section titled Programmed Logic The device is considered a multiple-student machine in the at ie that one digital computer using specialized input-output equipment handles the instruction of several students simultaneously The computer employed in PLATO 11 is ILLIAC a medium-speed digital computer with high-speed memory of 1024 words Because of this limitee memory capacity PLATO U can be used to instruct only two students though the program Io written to handle many more 2 In PLATO I3 the teaching logic is dotermined by programs within the central comlpeter Therefore changes in the teaching logic can be realized by modifying or rewriting cornputer programs No changing of equipment need be undertaken This flexibility in teachIng logic is particularly important in an exper 'mental program 3 As the machine teaches it automatically keeps detailed records on each student's progream through the material These large amounts of data may later be sorted and suitably proceased by the same central computer The combination of a system teaching large numbers of students concurrently and a digital computer for large-scale data processing should prove to be a powerful tool in educational research In PLATO rl executive control over the system as it instructs the students is exercised by a single central computer A teaching eystern such as PLATO II in which as many functions as possible are centralized in one fast large-scale computer has several advantages over one which duplicates many smaller special-purpose pieces of equipment These advantages pertain to the power and flexibility Inherent in the centralized system Description of Equipment Figure 1 shows the general organization of equipment in PLATO IL Exscutive control over the system is exercised by ILLIAC the University of nlinois' general purpose mediumspeed digital computer ILLIAC has a highspeed electrostatic memory of 1024 40-bit words and an auxiliary magnetic-drum storage of 10 240 words Its speed is typified by an add time of 75 microseconds and an average multiplication time of 700 microseconds The use of more modern computers which are both faster 1 PLATO n makes available to every student the considerable computational resources of a large-scale fast digital computer This can be of great advantage in some subject matters For example in certain branches of mathematics or physics the computer can relieve the student of numerous Student I atooSt udenL Switch Switch • AT2 Infformation Contro l Compute 2 Banfl Btzr ih Dnevier PAO Fig ZBitzer Braunfeld Lichtenberger 1 nAtmtdTahn W elt e T epbl hdi h General organization of PLATO UI PLATO A n Automated Teaching Device IRE Professional Group on Education 19 To be published in the 4 tronic switch slide selector connects the video uuipui irom any Qesired slide to the appropriate student's display The electronic book currently has a capacity of 61 slides to be expausded to 122 the slide selector can switch from any slide in the set to any other in about 1 millisecond In addition to access to the book each student is provided with him own individual electronic blackboard in the form of a storage tube ILLIAC by transmitting coordinates of indvi dual points may write characters figures graphs or the like directly onto any such tube The tube is then scanned by the television sweep and the video thus derived is mixed with that coming from the book Approximately 45 char acters per second can be written on the student's screen by this means 1 4 second is required to erase the entire contents of the storage tube and larger by at least an order of magnitude •tl should mairs 4I r-tmin% o M improved and expanded teaching logic Each student communicates to PLATO 11 by means of his own keyset The keymet resembling a typewriter has keys for all alphanumeric characters additional keys for special symbols can easily be added as needed Thus the student can transmit numerals words sentences or algebraic expressions to the machine The student controls the machine's presentation of material by means of special keys to be described in detail later The machine communicates with the students by means of closed circuit television Each student in provided with his own television screen on which the results of two separate video sources are- electronically superimposed These sources may conveniently be thought of as an electronic book and an electronic blackboard The electronic book is shared by all students though at any given time different students may be using entirely different parts of it It consists of a set of slides containing the instructional material which are continually scanned by a special flying-spot scanner cf Fig 2 On command from ILLIAC an elec- In general the electronic blackboard In used to display all material which cannot be pre-stored on slides because it Is generated in the course of the lesson itself For example when a question is asked on a slide the electronic blackboard makes it possible for the machine to display the student's answer superimposed on the slide in an appropriate place 5 Inch flying-spot cathode roy tube r r ISixty -on# IO1mm f4 5 lenses arranged In I If I Islide •hexgonal array so that reduced CRT roser isimaged on each of 61 SUiMe In Cll Slide cell with 61 slides positioned directly over end on' type photo multiplier tubes Photc- u t-pltrJ tubes SPro-amps video Svideo Fig 2 H agonol array of photo multiplier tube Jpra-amnp aeosmblioe to 61 position btobles swlitches The 61-slide simultaneous scanner for PLATO Il 20 I rLA_ I V ANl FigU3 T PROILIM eahn IL AN$ ER EAHPITV Aoifor9 OPLTO NEE SRP RESENTED IN DECIMAL NOTATION Programmed Logic COMBINING THE TEN DIGITS1 Whereas the material to be taught is contained on a set of slides the logical rules THUS THE SYMBOL '3 549' IS BY INTERPRETED TO MEAN governing instruction are determined by programs within ILLIAC These programs have been written to accommodate a variety of subject matters for example the computer program described here has been used for demonstration lessons in mathematics and French verb endings To change courses on the machine requires only that the slides of the electronic book be changed and a suitable parameter tape be read by the computer the basic program remains the same The PLATO II computer program requires hden through a fixed main 3 A io 9 102 04 10 49 ie 3 Xiooo5 100 4 X10 9 I O Wig 4 Text slide In addition to text slides the main sequence will contain slides on which one or more questions are posed to the student Spaces are provided on the slide for the student's answers cf Fig 5 A student must answer each question each student to proceed queston r he is peried Fig 5 correctly before hi is permitted to continue to sequence of slides and to answer correctly each question posed in the course of this mequence He may avail himself of supplementary material for each question of the main sequence which he finds troublesome help sequences Further details of the teaching logic are illustrated in Fig 3 and discussed in the following paragraphs QUESTION GIVE THE POITIVE NON-TRIVIAL DIVISORS OF 51 ORDER IN I Some slides of the main sequence contain only expository material text slides A text slide is shown in Fig 4 When a student has finished reading a text slide he pushes a button on his keyset labelled CONTINUE and the computer commands the slide selector to display the next slide of the sequence to this student Just as the continue button enables the student to advance through the material he can return to any previous slide by pushing the RE- Fig 5 VERSE key 21 Aniwer slide the next slide An attempt to bypass a slide with unanswered questions causes the cornputer'to i'hW a bell i dicatin a fault If at some later time the student should return to this slide via REVERSE his correct answers will again be displayed in their proper places presumably can work The rules for proceeding along a help sequence are tUe same as those governing the main sequence the student moves forward by use of the CONTINUE button but must answer successfully each question posed in the sequence The student types his answer to a question on the keyset As he depresses each key ILLIAC plots 0he corresponding character or display in the appropriate place on the television screen Upon completing his answer the student pushes the JUDGE button and the computer writes either OK or NO P-4xt to his answer of Fig 6 Methods of judglng answers are described below If the answer is ludged incorrect the student may submit another answer to the question To do this he first erases his incorrect answer by depressing the ERASE key and then types his revised answer on the key-et Upon request just as before the computer will judge the new answer Memory limitations of ILLIAC preclude the use of secondary help sequences Thus if a student cannot submit a correct answer to a help-sequence problem and asks for help once more the machine informs him that no addi tional help is available He in given two atternativea pushing REVERSE will return him to the problem for further consideration pushing HELP i e giving up will cause the machine to provide him with the correct answer At the end of a help sequence the CONTINUE button automatically returns the student to the main-sequence slide from which he came It is expected that he can now answer the mainsequence problem and proceed Otherwise a renewed request for help will cause the machine to provide the student with the correct answer as described A student who has asked for help may as QUJESTION GIVE he proceeds through a help sequence suddenly realize the answer to the main-sequence question By pushing the AHA button he will be returned to the main-sequence problem and may try his new answer If it is correct he is permitted to proceed in the main sequence Other- THE POSITIVE •-TRIVIAL DIVISORS OF 51 IN INCREASING ORDER d d2 Fig 6 T OK wise a renewed request for help causes the machine to return him to the point In the help sequence at which he broke off Thus a student is not required to go through supplementary material which he does not feel he needs NO Answers may be judged in many ways For questions having unique well-defined answers Answer slide filled-in and judged the computer compares the student's answer against the pre-stored correct answer For numerical answers tolerances may be specifled In more sophisticated judging routines the computer itself determines the correctness of a student's answer by using it In suitable calculations This approach is especially useful for questions permitting a variety of cbrrect answers Though not yet implemented it appears desirable that the computer not merely judge an answer but that it also examine each wrong answer for specific errors and route the student to special help sequences associated with each kind of error A student is allowed as many tries as he likes in answering a question In trying to answer a question a student is permitted to use the REVERSE button to review past material If he still has difficulty answering a question he may obtain supplementary material by depressing the HELP button This action causes the computer to transfer from the main mequence of slides to the beginning of the appropriate help sequence A help sequence designed to lead the student to an understanding of the main-sequ -e problem is provided for every question in the main sequence The help sequence may contain a review and reforrulation of previous materials pertinent to the question as well as suitable hints and suggestions Often a help sequence breaks the main-sequence problem down into a series of simipler problems each of which the student Finally in addition to exercising the executive control associated with instruction the program keeps accurate records of the mQves made by each student and the time elapsed at each move Thus a wealth of precise and reliable data is available concerning each student's 22 P rzrz' 04- u 2 the critical time limit Is 100 m WiIithis program no Input seconds Foroutiput eedopeations the a11M oporaionw and only two ' A a iister time the n data so to reveal procers these computer and theam ofet Information both about Important can _ -lessons cal limit One of thse-oeruant a given storage tube-has already been nutoned The Multiplexing Problem The problem of time-sharing Is more difficult Students tend to become confused if the computer does not respond immediately to their commands For example suppose a given student is typing his answer to a question The other operaton which 0s1 the critical limit is that of plotting more than one character on a storage tube For example a student may return to a page of the lesson which he has already entered answers His storage tube must first be erased and the old answers must then be plotted on it Wheni this came arises the program switches to a special mods of operation for the student In question called unfintshed buminess In unfinished business the computer is permitted to plot only one of the characters at a time before scanning all of the other keysets for possible inputs and performing any operations which theme inputs may require The student requiring unfinished business then is relegated to a position of lower priority and the computer completes the student's unfinished businees when it is receiving no Inputs The student's keyeet is locked out during this time so that he cannot enter informatlon Inadvertently In came of simultaneous unfinished business students are disposed of and is unaware of the computer's availability to him Then if other students have tied up the central computer some of the characters in the answer will be lost Care must be taken therefore to avoid situations where the computer Is tied up except for brief periods one by one in the order in which vutinished business was required for each of them It is thus possible for two students to share ILLIAC and except whebn unfinished business is required never experience delays due to equipMont tieup The multiplextn of several students onto one computer is complicated by the problem of bookkeeping and time sharing The bookkeeping problem is easily volved Moat of the program is written to handle one student All data for each student required by the program are kept together in a list When the computer must turn its attention from one student to another It saves thie currant information list and transfers the now information list from storage This transfer of data lists is necessary because ILLIAC lacks index registers ILLIAC's memory capacity in addition limits the current PLATO II to two sdnts The problem can be alleviated to some extent by the design of the equipment external to the computer By providing a small amount of control circuitry at each student position the system can perform some functions for the students in parallel For example the computer can tell the control circuit provided for a given student to erase him blackboard The computer is then free to do operations for other students while the control circuit completes erasing When the erase cycle is completed the control circuit so informs the computer Summary The important feature of PLATO U are 1 Each student may proceed through the material in a manner and at a speed of his own choosing subject only to the boundary condition that he must solve successfully a prescribed sequence of problems He may submit as many or as few answers to a question and seek am much or little supplementary material as he likes It was felt that one cannot kmow K priori the particular needs of a student at any po in his progress through the material as well as the student himself If the main sequence Is written for the best students the help mequences for the poorest ones then each student may use the HELP and AHA keyr to find for himself a suitable path in the spectrum between these two extremes Further solution of the time-sharing problem must be obtained by the computer program itself Clearly the computer cannot be tied to a given student more than a certain maximum time The reciprocal of this time limit defines a minimum rate at which the computer can accept information Let us determine this rate A student typing at a peak rate of 60 words per minute will generate one character per 200 milliseconds The computer must accept information at this rate for n students or at the rate of one character per 200 n milliseconds This time is the upper limit that the program can operate without interrogating the keysets In the computer program for PLATO II where 2 The machine will accept and display constructed answers as well as the more rostrictive answers to multiple choice questions The student is told as soon as he has submitted an answer whether it is correct or incorrect In the latter case the machine can indicate NO 23 3 WAthout revealing the correct solution Also sin'e a student cannot proceed before answering a question correctly the answer to any question may be used in the textual material of sub- qW'rn psW LD rue sequence Finally if the student reviews by means of the REVERSE key his answers to questions on previou slides VAgi automatlally displayed by the machine are slide sequence now assumes the character of athe tilled-in work book 3 The equipment as wel as the pro- grammed 1o0ic appear to be sufficiently vers tile so that one can change from one subjectmatter to another by simply replacing slides in the slide selector and giving the cornputer a new set of parameters Sequences of material Involving subject matter that varies as widely as number theory and French grammar have been prepared for use with thi same computer profram of the student's progress through the material It is hoped that such records after suitable processing on the machine will not only provide intm elm but wain of use in rev ig the mataeri•l• h't w Studies empl oing the PLATO U teaching logic indicate tLat the following additional teature would be an improvement with the current logic as'soon as the student gets a problem right no matter by what means he is sent on the net order of business However it now to seems clear that in determning whether to proceed the computer should' take into account how the student came to the correct answer to q-uestion Three factors seem to be of ir portance 1 How much time was required to solve the problem 2 How many wrong answers were sub mitted 3 Was help required On the basis of these three factors the computer should decide whether to go on to the next point in the main sequence or continue to dwell oua the current problem purposeIn of providingthe meatFor for the an following• research instrueducation points seem to be particularly important 1 The material is presented to every 2 At the end of any lesson thi experi menter has at his disposal a complete record 24